1. Field of the Invention
The present invention relates to a hybrid type driving apparatus that is equipped with an internal combustion engine and electric motor as the driving sources for a working machine, etc. and, more particularly, to a hybrid type driving apparatus that is constructed in such a way that a driving circuit can be commonly used between a motor that serves as the motive-power source for a working machine, etc. and a starter motor for the engine.
2. Description of the Related Art
In a working machine for agriculture use, there is known a so-called “hybrid” type engine-driven working machine that is constructed in such a way that the working machine can use the motive power of the engine and the motive power of a relevant motor. For example, in Japanese Patent Application Laid-Open No. 2001-161114, there is proposed a riding working machine that is constructed in the way that, in a case where the load of the working machine driven with an engine is small, the generator is driven with a surplus motive power of the engine and the surplus electric power of it is stored in a battery, where by, with the electric power that has been generated in the generator and the electric power that is supplied from the battery, the motors that are relevant to the working machine are driven. According to this riding working machine, since the load of the engine is maintained at all times high, it is possible to operate the engine with a high efficiency.
In the above-described hybrid type driving apparatus, it was necessary that driving circuits were respectively separately used for a starter motor for engine and for a motor that serves as a driving source for the working machine. When looking at from the viewpoint of simplifying this type of hybrid driving apparatus, by using as the starter motor the generator that serves as a motor and, at this time, commonly using an inverter circuit for starting and a regulator for the output of the generator partial common use of the circuits is certainly made (refer to Japanese Patent Application Laid-Open No. 2002-223594). However, the actual circumstance is that any contrivance has not yet been made when looked at from the viewpoint of commonly using the driving circuit.